Control devices which control the swing action of an air conditioning apparatus are known in conventional practice (e.g., Japanese Laid-open Patent Application No. 9196435). The control device sends to the air conditioning apparatus a control command causing the angle of a flap to vary. The flow of air blown out from the air conditioning apparatus is thereby shifted up and down, the air in the room is agitated, and deviations in the vertical temperature distribution in the space being air-conditioned are resolved. Particularly, in Japanese Laid-open Patent Application No. 9-196435, the width of a discharge port is adjusted to control the airflow rate of discharged air in accordance with the temperature of the discharged air. Specifically, the airflow rate is controlled so that the airflow rate is low when the discharge temperature is low and the airflow rate is high when the discharge temperature is high. This prevents a strong airflow from directly reaching the user when the discharge temperature is low, and reduces discomfort felt by the user due to a draft.